HVAC Load Calculator
ASHRAE-aligned heating, cooling, and ventilation sizing in one tool.
Calculate room-by-room heating and cooling loads, ventilation rates, and equipment selection in minutes — not hours. Every result is grounded in ASHRAE methodology and exports to a client-ready branded PDF.
What you get
Cooling & heating loads
Compute sensible and latent loads per ASHRAE methodology with envelope, infiltration, and internal gain components.
Ventilation per 62.1
Outdoor air rates calculated per ASHRAE 62.1 with occupancy and area-based components.
Equipment sizing reports
Recommend tonnage, CFM, and equipment selection with a signed-ready PDF you can hand to the contractor.
Unlimited calculators and AI. Pay only when you need a stamped PDF.
Every result tells you the exact clause behind the number.
Your firm's logo, project info, and citations — one click.
Frequently asked questions
Is this a Manual J replacement?
EngineSuite uses ASHRAE methodology suitable for commercial and complex residential projects where Manual J is too simplified.
Does it handle ventilation per ASHRAE 62.1?
Yes. Outdoor air rates follow 62.1 with occupancy density and area-based components.
Is EngineSuite free for students?
Yes. Students and EITs with a valid academic or professional email get free access to every calculator and the AI assistant. You only pay if you need a stamped PDF report.
Can I export branded PDF reports?
Yes. Every calculation can be exported as a one-click branded PDF with your company logo, name, and project metadata. Pro plans include unlimited exports.
Try it on your next project
Sign up free, run a calculation, and see the code citations for yourself.